1. Field of the Invention
This invention relates to determining the number of teeth of a flywheel, by waveform analysis of flywheel tooth speed, or alternatively by engine cycle signals.
2. Description of the Prior Art
In the aforementioned application of Stick et al, the utilization of flywheel teeth to determine speed of an internal combustion engine in order to accommodate sophisticated internal combustion engine diagnostics, and the manner of determining the number of teeth in the flywheel for such speed computations is set forth. In that application, the number of teeth on the flywheel is determined by counting the teeth through a full cycle or engine revolution as indicated by a proximity sensor mounted on a member (such as a rocker arm) of the engine so as to provide a signal at an identical point in successive engine cycles.
In some instances, a suitable proximity sensor might not be mounted on an engine where certain diagnostics are to be performed. Particularly if only one or two tests requiring speed are desired, it may not be worthwhile to mount a transducer suitably on an engine, particularly if such engine requires hole drilling or other modifications in order to accommodate the transducer.